Piano World Home Page Forums Our Most Popular Forums Piano Tuner-Technicians Forum Tuning pin replacement size for loose tuning pins?

I have a client with a nice German Schilling Upright. The condition of the piano is overall quite well. The steel strings look clean and not corroded, the bass strings look and sound good. Keyboard, action, hammers... all are rarely used.

The only one but severe problem are loose tuning pins. The current tuning pins are 60 mm x 7.0 mm. Some are just a bit on the loose side but still tuneable, other are extremely loose, so that they don't hold a tuning at all.

What size would be adequate for replacement tuning pins?

An application of low viscosity CA glue will probably be sufficient.

I am with beethoven on the thin CA glue as the first try repair. Lay the piano on its back. Use an extender tube on the bottle.

If after letting all the glue set up for a day, the pins still won't hold, go up by two diameter increments from the present pins. Except for the top octave or so where maybe one size increase would be better because really tight treble pins make tuning slow.

I agree with Ed completely!

+1

I know techs that change the tuning pins on site without putting the piano on its back. 1 size is enough usually 2 sizes you need to ream

if the bad pins are on lines the pinblock is in cause

piano at pitch and good pin setting allow most pianos to be tuned, unless the pinblock is at fault or the holes ovalized by time or brutal tuners (benders)

I consider that if the hammer does not come back, I can set the pin and string with enough stability.

Tapping 1-2 mm can buy about 10 years on a good quality block.

I would not take the risk of compromizing the wood (gluing the fiber that usually serve to lock the pins)

It may be possible that the thread on the pins have wear but the block is good.

Dear Upright - Just curious if this is your first time repinning a piano?

I concur with the others who encourage you to try CA glue first. Just make sure you purchase a thin mixture - I use the product that Schaff Piano Supply sells, and it works well.

If that doesn't do the trick, repinning may be in order. If you haven't done a repinning job, I'm sure those who have would be glad to give you some tips to help you attain satisfactory results. Chuck Behm

To my knowledge, notwithstanding their technical merits, pinblock treatments, especially CA glue, are much more frowned upon in Germany than in America.

Hi Mark - That's interesting to know - I wasn't aware of that, but I'm not surprised at all.

I first heard about using CA at a lunch break during a technician's meeting and I remember thinking (and commenting on) how dumb I thought the idea was. Supergluing a pinblock! I seemed ridiculous to me.

Then, a few months later, I had occasion to try it. I had a little old lady customer with a little spinet that she loved with pins so loose some of them would turn counterclockwise by themselves when you let go of the hammer. She was on a fixed income, so repinning was out, and the pins had already been tapped in. Using Lundford's pinblock restorer was out, in that she lived in a tiny apartment where leaving the piano on its back for an extended time was out.

Long story short, I tried the CA treatment, only charging her for the cost of the glue. I told her it was an experimental procedure for me, and therefore I was willing to do it for no labor charge.

It worked very, very well, and the piano has been stable ever since, with pins which hold well.

Faced with a piano with loose pins, I ordinarily offer options, from CA treatment all the way to a new pinblock, pins and strings, with a huge difference in price range. I tell my customers that I've observed that CA treatment typically will give 75% of the benefit (in terms of torque) of repinning at a fraction of the cost.

Anyway, I can well understand if there's regional skepticism. I wouldn't particularly want to be the one technician using a procedure that everyone else in my area frowned upon. For example, here in the U.S. (and elsewhere I would imagine) use of the metal tuning pin sleeves intended for shimming loose pins are pretty much universally frowned upon. Using them would pretty much be the kiss of death for your reputation - at least among other technicians.

Thanks again for the heads-up. A good bit of information to keep in mind in the future. Chuck

It is also considered BS here, in fact I never seen one installed in a piano.

The idea is not to "glue" the pin, but probably to gain some resiliency in a wood that is mushy.

The reports I had confirmed the absence of the usual feedback from the pin. Now if it allow cheap grade pianos to be made more or less tuneable it may be a good sercice to the owner...

DUe to the way I see the tuning lever manipulations, I believe that part of the pinblock wear is due to tuners.

only very low quality pinblock under hard moisture conditions should fail, with good tuning methods.

Isaac - Here in the midwest with frigid winters and humid summers, the effects of dry, heated air one season and dripping humidity the next can really affect pinblocks, no matter how good the piano. Granted, cheaply made pianos are bound to fail first, but I've seen very good pianos with pins that won't hold, due to a pinblock that has severely dried out.

Your comment about the absence of usual feedback from the pin (I think you're talking about CA) is correct. Pins treated with CA have a different feel from repinned pianos, which in turn feel differently than pianos which have an all-new pinblock and size 2 pins. I prefer the feel I get with a new pinblock, but I also charge 30 times as much for going that far than I do for an application of CA. In the end, for the customer the CA treatment can be very satisfactory, in that his piano will be much more stable than before the application. Chuck

A hole (bush) is oval. Because a string have a pressure towards a floor (piano).
You can fill in a hole the CA or increase the size of a pin.
sometimes corrugated cardboard shim will a aid

I work on plenty of old pianos that have not visible oval holes.

Out of quality, and caution when tuning, it may be climate related, certainly.

Under normal conditions, the hole can oval a little, but not deeply, the force is reflected farther +- on the opposite side by the pin, so the bottom of the hole does not take stress as much, and of the pin can grip a little there, even with a slightly oval entry the pin can be set.

Moving back and forth or pushing strong on the hole will wear it at its deepest, and sand the bed of the key, the portion where it lay.

That is why a perfect knowledge of the rotation plane is prerequisite to tuning. So to apply force where it is not harmful, I. e, on the pin itself or the portion of hole that is not used for setting the pin.

No need to distort the essence of physical phenomena fixing of a pin.
I think unimportant to consider: "Where a delete wood more in a bush or the upper part of the hole pinblock?".
Corrugated cardboard shim provides increased friction between a pin and wood hole

I agree, but what happens too is the wear of the thread on the tuning pin.

We do experience a cool climate so my experience in shot pinblocks is limited.

Now of course wood resiliency migrates farther from the pin with age. Only friction allows to tune then, but strangely even on very old pianos with original pins (Viennese forte for isntane) I could obtain a very firm pin setting (after numerous lowering/loading of the pin stress.

It is a "knot" with a balance of stresses, and the pin is an active part of the whole.

It is harder to learn to "tune the pin" than to tune the string only, and one need to base the setting on the amount of resistance coming from the upper wire segment.

Once that resistance is balanced by the pin's and pinblock resiliency you are directly impacting the sounding length, so the impression in the lever is that the tuning pin and upper segment are "transparent".

I have find no other mean to fine work the string.

Retuning often mean restitution of the balance of forces, and if not enough the whole thing can be put back under the correct tension/pitch without modifying the original balance.

Thanks,Isaac
I would want see this original pins (Viennese forte for isntane). If are you have foto or a link
Regards,Max

I am not sure I have a picture.

They are made with wrought iron, so they cannot be tense much they may break if too much stressed.

very little length goes in the pinblock.

Despite that they can be set "strong" as piano tuning pins.

P.S) while it is not absolutely recommended to install very firm pin setting as iron strings may need to be tuned more often (?) they also are used by Baroco ensembles and different temperament may be asked.

A colleague who specialized in tuning historical instruments told me that we "cheat" when tuning them, the idea is to give "an impression of justness" it is really up to the tuner to accept or not some intervals, and play with the unisons.

Is it less 30 mm in a pinblock?

Probably less , yes

Dear Chuck,

thank you for your comment. This is not my first time of repining. I did complete restringing as well as partial pin replacements. I also used CA in a few cases. But I wanted to know others opinions on the topic.

I know the rule of thumb to go up two sizes from Reblitz. But as the pins can be bought here in Germany in size steps of 0,05 mm, I wanted to know others rules of thumb and what they use, in different cases.

And I am glad, this developed into an interesting discussion.